When doing AOS if you've been married at time of the interview for less than two years you will be granted a two year conditional green card. You have to file to remove the conditions in two years to be granted a full blown 10 year green card. The removing of conditions (ROC) is fairly simple but a pain in the ass as you pretty have to resubmit as if you were applying for AOS again ($700 fee, bank statements, leases, insurance, go through biometrics, maybe an interview, etc...) and it is taking a long ass time (I submitted for ROC in June 2018 and am still waiting for it to be approved). When I applied for AOS I had been married for about 12 months, the whole AOS process was a lot faster so my interview was at 1 year and 4 months of being married. Now the process is taking a lot longer (a year or more) but if you have been married for two years at the time of your AOS interview, then you avoid the ROC nonsense.